This invention relates to a suspension system for a bicycle or the like to improve the riding comfort thereof. More particularly, the invention relates to a shock absorbing system for use at the seat, front forks, frame or other location on a bicycle to form a suspension system to dampen shocks incurred during riding.
The comfort of the ride on bicycles or other similar vehicles has escalated in importance as the popularity and use of such vehicles has expanded. For example, bicycles are now manufactured which are known as mountain bikes or ATB's (All Terrain Bicycle) which are constructed to be used in off-road environments. In these particular situations, the comfort of the ride is particularly important. The comfort is also important with road use of bicycles as the length of the ride is usually significantly longer.
A variety of suspension systems have been developed for bicycles or the like. These include shock absorbing means coupled with the frame of the bicycle and to the wheels thereof so as to absorb shocks imposed on the wheels during riding. These systems usually provide relative movement between the wheels and the frame of the bicycle.
Other proposed systems to isolate shocks imposed on bicycles and similar vehicles have included the mounting of coil springs onto the bottom of the seat on which the rider rests or to the seat frame to cushion shock to some degree. Other systems provide relative movement between the seat of the bicycle on which the rider will be supported and the frame of the bicycle, to thereby absorb shocks imposed on the bicycle and to provide a smoother ride. In such systems, disadvantages have been found to exist in that exposure to the atmosphere subjects the apparatus to corrosion which will limit the life expectancy and functioning of the apparatus. Similarly, attempts to limit rotation of the shock absorbing posts in such apparatus include structure which is also exposed to the environment and may gather dirt or other debris, thereby inhibiting shock absorbing capabilities. It has also been found that the device has no dampening means by which the rider can vary the amount of dampening provided by the system and are therefore not be effective over a wide range of riders which may utilize the system and over a broad range of road or off-road conditions. Alternatively, some suspension designs include relatively complex toggle systems to yield relative movement between the wheels of the bicycle and the frame. These systems have not provided the performance characteristics desired.
The various designs have been found to be disadvantageous for various reasons such as binding or restricted movement due to non-lubrication, exposure to atmospheric conditions, lack of adjustability or flexibility in the control of the shock absorber characteristics. Other problems with prior art suspension systems are found in the strength and durability of the systems in use with bicycles or the like. For example, a shock isolation system adapted to mount the seat or front forks of the bicycle thereon is subjected to various loading including lateral loading which imposes structural requirements to meet such loads. In attempting to provide the structural strength in the shock absorbing system, the weight of the shock absorbing system has proved to be prohibitive in view of the strong emphasis placed upon decreasing the weight of the bicycle. At the location of the front forks, it is imperative that the structural integrity of the shock isolation system be maintained, while not increasing the weight of the bicycle to any great degree. Various prior art systems which have been developed for use at the front fork location of the bicycle have not provided a great deal of shock absorbing capabilities, or have been complex and generally ineffective.